<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <meta http-equiv="X-UA-Compatible" content="ie=edge" />
    <title>Document</title>
  </head>
  <body>
    <ul class="clearfix">
      <li>first-step</li>
      <li class="active">second-step</li>
      <li>thrid-step</li>
      <li class="active">fouth-step</li>
    </ul>
  </body>
  <style>
    ul,
    li {
      margin: 0;
      list-style: none;
    }
    ul {
      margin: 0;
      padding: 0;
      display: inline-block;
      background: #fff;
    }
    .clearfix:before,
    .clearfix:after {
      display: table;
      line-height: 0;
      content: '';
    }
    ul > li {
      display: inline-block;
      position: relative;
      margin-right: 5px;
      line-height: 18px;
      list-style: none;
      padding: 12px 17px 10px 30px;
      background: #efefef;
      zoom: 1;
      cursor: pointer;
    }

    ul > li:first-child {
      border-radius: 4px 0 0 4px;
      padding-left: 30px;
    }
    ul > li::before {
      content: '';
      position: absolute;
      left: 0;
      top: 0;
      height: 0;
      width: 0;
      border-bottom: 20px inset transparent;
      border-left: 20px solid #fff;
      border-top: 20px inset transparent;
    }
    ul > li::after {
      position: absolute;
      right: -20px;
      top: 0;
      height: 0;
      width: 0;
      border-bottom: 20px inset transparent;
      border-left: 20px solid #efefef;
      border-top: 20px inset transparent;
      content: '';
      z-index: 2;
    }
    ul > li.active {
      color: #fff;
      background-color: #007acc;
    }
    ul > li.active::after {
      border-left-color: #007acc;
    }
  </style>
</html>
